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THE CERTIFICATE BEHIND THE CONNECTION

TLS certificate checker.

Inspect SSL/TLS certificates for any public domain or subdomain.

Checks HTTPS on port 443, including subject alternative names, validity dates and the presented chain.

SSL certificate

TLSv1.3

mail.nationmark.com · 202.53.128.161:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. Peer certificate subjectAltName did not match expected name `mail.nationmark.com'

Certificate verification failed

Subject
C=HK L=Kwun Tong O=Nationmark Service Centre Ltd. CN=mail2.nationmark.com
Issuer
C=US O=DigiCert Inc OU=www.digicert.com CN=Thawte TLS RSA CA G1
Valid from
2025-12-15T00:00:00+00:00
Expires
2027-01-15T23:59:59+00:00
Days remaining
69
Serial (hex)
098816F6A074CF950FF96C00D3D0E523
Signature
RSA-SHA256
Public key
RSA 3072

Subject alternative names (SAN)

DNS:mail2.nationmark.com

SHA-256 fingerprint

75:27:69:0C:38:40:3D:1D:68:42:B3:DC:1F:64:03:E2:4D:60:CC:ED:2B:B9:7D:57:26:05:C0:87:BF:A6:0F:E6
Certificate extensions & PEM
authorityKeyIdentifier
A5:8C:FE:32:CC:EB:0F:2C:D4:19:C6:08:B8:00:24:88:5D:C3:C5:B7
subjectKeyIdentifier
68:51:E5:67:86:D2:B0:E0:3E:EC:6D:2E:2B:09:4A:9A:21:5F:4C:7F
subjectAltName
DNS:mail2.nationmark.com
certificatePolicies
Policy: 2.23.140.1.2.2 CPS: http://www.digicert.com/CPS
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
crlDistributionPoints
Full Name: URI:http://cdp.thawte.com/ThawteTLSRSACAG1.crl
authorityInfoAccess
OCSP - URI:http://status.thawte.com CA Issuers - URI:http://cacerts.thawte.com/ThawteTLSRSACAG1.crt
basicConstraints
CA:FALSE
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 4C:63:DC:98:E5:9C:1D:AB:88:F6:1E:8A:3D:DE:AE:8F: AB:44:A3:37:7B:5F:9B:94:C3:FB:A1:9C:FC:C1:BE:26 Timestamp : Dec 15 03:07:21.057 2025 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:4C:1A:44:BF:70:84:E2:59:70:D3:E1:30: EC:BB:66:57:7C:7B:52:BA:EE:DA:96:27:6F:30:AF:D2: 3F:E5:FF:42:02:20:27:9D:92:A2:82:B0:A7:DE:DB:40: CE:6B:AD:8E:CD:7F:0A:4B:91:8C:56:9D:9C:E6:6A:59: D6:E5:65:F5:9F:B7 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1C:9F:68:2C:E9:FA:F0:45:69:50:F8:1B:96:8A:87:DD: DB:32:10:D8:4C:E6:C8:B2:E3:82:52:4A:C4:CF:59:9F Timestamp : Dec 15 03:07:21.733 2025 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:15:06:D4:55:1B:E4:63:02:C8:08:1F:17: 30:DE:4C:75:C6:2F:44:C4:82:79:2E:AF:D6:09:CA:7D: F7:63:C8:FD:02:20:44:3E:83:DE:01:0C:6D:9F:81:D5: F2:29:5B:FE:A2:69:1E:48:EE:CA:0F:A9:14:41:7D:5F: 2E:C1:56:F2:73:AB Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 60:4C:9A:AF:7A:7F:77:5F:01:D4:06:FC:92:0D:C8:99: EB:0B:1C:7D:F8:C9:52:1B:FA:FA:17:77:3B:97:8B:C9 Timestamp : Dec 15 03:07:21.299 2025 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:A7:46:54:1E:D9:80:0A:B0:6C:83:74: 16:53:26:30:8E:59:97:00:00:35:39:06:C9:5E:65:6F: A6:04:03:55:80:02:21:00:C5:DA:3D:EE:6C:89:8F:63: 44:01:8F:5F:B0:22:93:6A:22:F5:DE:BE:74:32:3C:C7: 53:75:2E:49:25:64:9E:59
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-11-07T21:26:45+00:00

Server-presented chain · 1 additional certificate

Chain certificate 1

Subject
C=US O=DigiCert Inc OU=www.digicert.com CN=Thawte TLS RSA CA G1
Issuer
C=US O=DigiCert Inc OU=www.digicert.com CN=DigiCert Global Root G2
Valid from
2017-11-02T12:24:25+00:00
Expires
2027-11-02T12:24:25+00:00
Days remaining
359
Serial (hex)
090EE8C5DE5BFA62D2AE2FF7097C4857
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

4B:CC:5E:23:4F:E8:1E:DE:4E:AF:88:3A:A1:9C:31:33:5B:0B:26:E8:5E:06:6B:99:45:E4:CB:61:53:EB:20:C2
Certificate extensions & PEM
subjectKeyIdentifier
A5:8C:FE:32:CC:EB:0F:2C:D4:19:C6:08:B8:00:24:88:5D:C3:C5:B7
authorityKeyIdentifier
4E:22:54:20:18:95:E6:E3:6E:E6:0F:FA:FA:B9:12:ED:06:17:8F:39
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
basicConstraints
CA:TRUE, pathlen:0
authorityInfoAccess
OCSP - URI:http://ocsp.digicert.com
crlDistributionPoints
Full Name: URI:http://crl3.digicert.com/DigiCertGlobalRootG2.crl
certificatePolicies
Policy: X509v3 Any Policy CPS: https://www.digicert.com/CPS
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

One endpoint on port 443. Server-presented chain; no revocation, OCSP, CT or full TLS security scan.

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